The tide gauge reads three point seven meters. It has always read three point seven meters when I come to work in the morning. This is not a coincidence. I made sure of it.

Dr. O'Brien says I didn't make sure of anything. "You came here because the posting asked for someone who understands water," she told me, her pen hovering over a clipboard that contained eleven pages of questions she hadn't yet asked. "You didn't choose the water. The water was chosen for you."

She's wrong. Or she's right. I can't tell the difference anymore.

It's been four months since I arrived in Cork. Four months since the Meridian dropped anchor in the harbor and I stepped onto the dock for the first time since—or before—I can't remember which comes first, the memory of the dead or the memory of the living.

Emily. Susan. Antonio.

Three names on a page. Three people who stopped and didn't start again. I've written their names in my notebook so many times that the handwriting has changed shape—become something I don't recognize, like a stranger signing their name on a envelope I'm supposed to deliver.

Tom Cahill, it says. Tom Cahill, the tide keeper. Tom Cahill, the man who survived.

But survival is not a word I use. Survival implies a choice. I didn't choose to survive any more than I chose to be on that ship, or to know Emily's music, or to watch Antonio's hands curl around that wrench like they were still trying to hold something that had already slipped away.

"I don't remember it the same way every time," I told Dr. O'Brien last Tuesday. I was sitting in her office, which smelled of old paper and lavender—the kind of smell designed to make you feel safe and failing. "Sometimes Emily dies in her sleep. Sometimes she disappears. Not dies—disappears. Like she was erased between one second and the next."

She wrote something down. I couldn't see what. "Which version do you believe?" she asked.

"I chose the first one."

"Chose."

"It's easier. The second one is simpler. And simple things are harder to live with."

She looked at me for a long time. The kind of look that measures not what you've said but what you've left out. I wondered what she found missing. I wondered if she was looking for the same thing I've been looking for since I got here—the gap between the tide that comes in and the tide that goes out, the moment where water remembers it was once rain and hasn't yet decided to become sea.

I came to Cork to measure tides because they are the most honest thing I know. They don't choose to rise. They don't decide to fall. They respond to forces larger than themselves—the moon's gravity, the Earth's rotation, the pull of places they've never been.

Is that what I am? A tide? Something that responds without choosing, moves without deciding, arrives without intending to?

The gauge reads three point seven meters. I didn't set it. But it reads what I need it to read.